16-cell

Noun

16-cell (plural 16-cells)

1. A four-dimensional polytope, analogous to an octahedron, whose sixteen bounding facets are tetrahedra.
   • The remaining 8, as before, are the vertices of the complementary 16-cell (see Figure 9). In Figure 7, these 8 points have been blackened, but not joined, because the 16-cell has longer edges; diameters of octahedral facets of the 24-cell.1995, Harold Scott Macdonald Coxeter, “Paper Three: Two Aspects Of The Regular 24-Cell In Four Dimensions”, in F. Arthur Sherk, editor, Kaleidoscopes: Selected Writings of H.S.M. Coxeter, page 32
   • This polytope has 16 tetrahedral cells, and for this reason it is called the 16-cell.[…]The 16-cell has 24 edges that are the diagonals of the 24 square faces of the hypercube. (Since we are selecting alternate vertices of the hypercube, we only get one diagonal for each square face.)2002, Gabor Toth, Glimpses of Algebra and Geometry, 2nd edition, page 385

   Synonyms:

   4-orthoplex, 4-demicube, 4-hemicube, demihypercube, demitesseract, hexadecachoron, hexadecahedroid